Deprecate implicit `int` to `bool` conversion for integer literals

[Dmitry Olshansky]

On Saturday, 11 November 2017 at 14:54:42 UTC, Jonathan M Davis 
wrote:
> On Saturday, November 11, 2017 13:40:23 Michael V. Franklin via 
> Digitalmars- d wrote:
>> What's the official word on this: 
>> https://github.com/dlang/dmd/pull/6404
>>
>> Does it need a DIP?
>>
>> If I revive it will it go anywhere?
>>
>> What needs to be done to move it forward?
>
> It probably needs a DIP, since it's a language change, and 
> based on what Walter has said in the past about this topic, I 
> don't know how convincible he his. I think that most everyone 
> else thought that it was terrible when code like this
>
> auto foo(bool) {...}
> auto foo(long) {...}
>
> foo(1);
>
> ends up with the bool overload being called, but Walter's 
> answer was just to add an int overload if you didn't want 1 to 
> call the bool overload.

Yeah, this is bad.

However, I’d hate to rewrite things like:

if (a & (flag1 | flag2))

to

if ((a & (flag1 | flag2)) != 0)

When the first is quite obvious.